1. Field of the Invention
The present invention relates to an image forming apparatus including a monitoring unit for monitoring an output voltage.
2. Description of the Related Art
An image forming apparatus is known which includes a monitoring unit for monitoring a power failure and an instantaneous voltage drop (brownout) (Japanese Patent Application Laid-Open No. 2009-213042). The image forming apparatus discussed in Japanese Patent Application Laid-Open No. 2009-213042 includes a power monitoring unit for detecting a power failure and an instantaneous voltage drop based on a drop of an input voltage. The power monitoring unit is an electrical circuit which outputs a predetermined signal to a controller if the input voltage falls below a predetermined threshold value. When a central processing unit (CPU) of the controller receives the above-described predetermined signal from the power monitoring unit, the CPU executes initialization processing on the image forming apparatus, and then sets the image forming apparatus in a state where power supply is stopped, i.e., a plug is disconnected from alternating current (AC) power. Then, when power is supplied to the CPU of the controller, the CPU supplied with the relevant power executes activation processing.
In the above-described image forming apparatus discussed in Japanese Patent Application Laid-Open No. 2009-213042, if a power failure occurs, power supply to the controller is once stopped. Therefore, since processing for activating the controller is required to restore the image forming apparatus, it takes time until the image forming apparatus returns to an operable state even after the power failure is resolved.